This invention relates to a charging mechanism of a camera shutter. Generally, charging a camera shutter for carrying out the exposure operation is carried out simultaniously with film advance by the operation of the film rolling-up mechanism of the camera. Because of manufacturing tolerances it is essentialy impossible to make the time point of finishing the charging the same for each charging operation. In order to solve this problem, the following method is generally attempted; namely, by providing a region to enable both mechanisms to actuate even after finishing the charging, so as to make both mechanisms perfectly charge by stopping both mechanisms in said region at the time point when one frame of the film has been advanced. However, to cope with the miniaturization of modern cameras, a miniaturization at the portion not directly relating the shutter performance becomes imperative, so that it is required to reduce said region in said charging mechanism.